Bifocal spectacles and eyeglasses.



` G; W. BAKER. BIFOGAL SPECTACLES AND EYEGLASSES. APPLIOATIQN P ILED-JULY 25,1912.

' jkl/612' for dBm/- er Patented Jan. 7, 1913.

, UNITED srATEs PATENT orrroia.

' ,GEORGE Wfrsron BAKER, or NORTH SYDNEY, NEW scorn wenns, a'o'srnnma.

BIEOCAL SPECTACLES AND EYEGLASSES.

intacts.

Specification of Letters Patent.

Patented Jan. 19,13.

Application filed Jfuy 25, 1912. Serial No. 711,536.

ain, residing in New South tVales, (temporarily at Katannin, near Perth,lWestern Austral1a.,) Australia, and whose post-'office vaddress isEnult Milner-s Crescent lWolltstonecraft, North Sydney, New Southllales, Australia, ophthalmic surgeon, have invented' certain new andluseful Improvements in Bifocal Spectaclesand Eyeglasses, of which thefollowing is a specification.

This invention which originally formed part of my co.-pendng applicationSerial N o. 590489, relates to improvements in spectacles having bifocalglasses -orlenses.

.Users of bi-focal glasses,h in which the lenses have been tixed in thespectacle or like frame, have been under considerable disadvantagesbecause the auxiliary'power or close vision segments or sectors of thelenses, although conveniently placed for reading and similar purposes,have been an impediment 'to the wearers vision when walking forinstance, because they prevent a clear and continuous view of theground. To obviate the above disadvantagesbifocal lenses 1 haveeitherbeen pivotally' mounted directly 0n parts of the spectacle frame in amanner that when they are to be reversed they must necessarily be turnedtogether, or they have been each mounted in separate auxiliary' framesswiveling on the main frame.

The main object of this invention is to obviate the luse of thesecondary or auxiliary frame while allowing each lens to be revolvedseparately and independently of the other.

The lenses are so mounted in or upon the spectacle 0r other frame insuch a way that each, independently of the other, can be partiallyrotated or moved so as to bring either the high or low power sectors,that. is the close or distant vision lenses, or portions of lenses, intothe field of vision, or so that said lenses will focus in the desireddirection.

In order that the invention may be readily understood, it will bedescribed by reference to the accon'lpanying drawings, in whichz- Figurel 'represents a pair of bifocal spectacles having circular bi-focallenses arranged so thatthey can be turned around in the same verticalplane through about one half of their circumference. Fig. 2 1s anelevation of a device for rotating a lens,

modified device for turning the lens attached, and Fig. lis an elevationof part of the lens in .theFig 3.

The same reference numerals indicate the same or corresponding parts inall the iigures..

l and 2 represent the two segments of a bi-focal lens. Each. lensis-circular and is mounted in a pair of circular rims in such a way thatit canbe'turned around or through an angle of 180 degrees as indicatedby dotted lines in Fig. 1. To admit of this movement the lens ismountedcomparatively loosely in the rim instead of being gripped tightly or setin position as in the case of ordinary' spectacles. To facilitate therotafloor from being obtained. By, `however,

turning it over into the position indicated on the left hand side of thespectacles, a clear field of vision is at once afforded through the lowpower or distant vision segment l and consequently the spectacles can beused with perfect comfort and safety for walking about.

It will be obvious that the construction of the glassesillustrated inFig. 1, can be modilied inV various details without departing from theessential-feature of the invention. For example, instead of using asmall knob or projection 3.on the face of the lens, a du plex clip canbe arranged toproject from the lens on each side of the rim and berestrauied from being moved past a certain point by coming intoengagement with a small stop or enlargement 6- on the rim.

suitably secured to the lens, as for instance by the rivet 33.

Having thus described inventionand thev best means I knowof car- .F ig.3 is a section of part of a lens with a the nature .of 'myY sal sa y

gg Les Tying the same into peeticai effect, l 1,3 vldlm. v

l. ln speetselesthe combination of a. lens frame, a nose. bridge pieceattached to the fra-ine, a. pair of bioenl lenses mm'ebly mounted onsaid frame and means 'for rotatingr each lens independently of oneanother, and in the vertical plane of the frame.

2. n spectacles, the Combination of a lens frame, a nose bridge pieceatt-ached to the frame, a pair of bi-fooal lenses movablyl new 'mountedon said frame and means comprising a projection carried by each lens forrotating the lens independently of the other, and in the vertical planeof the frame.

.ln testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

GEURGE WSTON BAKER.

Witnesses:

Gr. ALEC COOPER, L. TILSLEY BAKER.

